Family: Bradypodidae
   General information and anatomy of the three toed sloth.
   http://animaldiversity.ummz.umich.edu/chordata/mammalia/xenarthra/bradypodidae.html

Family: Megalonychidae
   General information and anatomy of the two toed sloth.
   http://animaldiversity.ummz.umich.edu/chordata/mammalia/xenarthra/megalonychidae.html